Telomere length is measured using Southern blotting of the chromosomal terminal restriction fragments (TRFs) released by endonuclease digestion in cells from yeast to human. In the budding yeast Saccharomyces cerevisiae, XhoI or PstI is applied to cut the subtelomere Y′ element and release TRFs from the 17 subtelomeres. However, telomeres from other 15 X‐element‐only subtelomeres are omitted from analysis. Here, we report a method for measuring all 32 telomeres in S. cerevisiae using the endonuclease MmeI. Based on analyses of the endonuclease cleavage sites, we found that the TRFs generated by MmeI displayed two distinguishable bands in the sizes of ~500 and ~700 bp comprising telomeres (300 bp) and subtelomeres (200–400 bp). The modified MmeI‐restricted TRF (mTRF) method recapitulated telomere shortening and lengthening caused by deficiencies of YKu and Rif1 respectively in S. cerevisiae. Furthermore, we found that mTRF was also applicable to telomere length analysis in S. paradoxus strains. These results demonstrate a useful tool for simultaneous detection of telomeres from all chromosomal ends with both X‐element‐only and Y′‐element subtelomeres in S. cerevisiae species.

中文翻译：

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来自 MmeI 的完整端粒集的同时可视化在酵母中生成了终端限制片段。

端粒长度是使用从酵母到人类的细胞中核酸内切酶消化释放的染色体末端限制性片段 (TRF) 的 Southern 印迹法测量的。在出芽酵母Saccharomyces cerevisiae 中，应用Xho I 或Pst I 来切割亚端粒 Y' 元件并从 17 个亚端粒中释放 TRF。然而，分析中忽略了来自其他 15 种仅含 X 元素的亚端粒的端粒。在这里，我们报告了一种使用内切核酸酶Mme I测量酿酒酵母中所有 32 个端粒的方法。基于对内切核酸酶切割位点的分析，我们发现Mme产生的 TRF我展示了两个可区分的带，大小分别为 ~500 和 ~700 bp，包括端粒 (300 bp) 和亚端粒 (200–400 bp)。改良的Mme I 限制性 TRF (mTRF) 方法概括了酿酒酵母中分别由 YKu 和 Rif1 缺陷引起的端粒缩短和延长。此外，我们发现 mTRF 也适用于S. paradoxus菌株的端粒长度分析。这些结果证明了一种有用的工具，可以同时检测酿酒酵母物种中所有染色体末端的端粒，其中包含仅 X 元素和 Y' 元素亚端粒。